If they can actually do 2 or 3 times the energy density of Li-ion for tens of thousands of cycles for the same price or less, scalably, then it's basically a revolution. Electric cars, amongst a whole bunch of other things, become tremendously viable all of a sudden. Integration of ultracapacitors could, I guess, solve the charging problem encountered by current electric cars (by which I mean driving 400 miles will probably take 3 days because charging is such a slow process).

Some very informative details are provided on the mechanics of batteries, accompanied by good points on opportunities for improvements in the near future.

I had wondered if the equivalent of a Moore's law was possible with batteries. This development seems to provide some reasonable hope for greater efficiencies to be realized.

200 KM distance on pure electricity at a third of a cost sounds quite impressive actually; would probably make electric city driving practical, at least for West/Central Europeans, the NE and Bay Area of the US, large urban, middle class areas of the developing world....

I think other articles discussing alternative energy should emulate this format, and approach in providing details. Specifically the ones dealing with solar energy - It always seems such articles run away from providing stats on efficiencies, like PVs with incidental light and potential advances, along with what could be accomplish with concentrators, or thermal solar..

Go to the Sion Power site. We'e not there yet, but I do think there is light at the end of the electric car tunnel. And I would be surprised if it took the six years or so that Planar is predicting. With so many competitors pushing each other I expect the race to heat up.

Not mentioned here, but thin films should also reduce recharging times as dimensions decrease and gradients increase. I worry that these batteries are likely to need cooling circuits as they get smaller, though.